Spiral stairway



(No Modell.)

' H. F. A. BORNEMAN 8v J. DAAB.

SPIRAL STAIRWAY.

No. 485,449. l Patented Novi 1', 189,2.

HERMAN F. A. BORNEMAN AND JACOB DAAB, OF COLUMBUS, OHIO.

SPI RAL STAIRWAY.

SPECIFICATION forming part of Letters Patent No. 485,449, dated November 1, 17892.

Application iiled April 2,1892. Serial No. 427,431. (No model.) i

To all whom it may concern:

Be it known that we, HERMAN F. A. BORNE- MAN and JACOB DAAB, citizens of the United States, residing at Columbus, in the county of Franklin and State of Ohio, have invented a certain new and useful Improvement in Spiral Stairways, of which the following is a specification.

Our invention relates to the improvement of spiral or winding stairways; and the objects of our invention are to provide a winding or spiral stairway of superior construction, to construct the same in a neat, strong, and durable manner, to provide improved means for supporting the steps from a common standard, to provide improved means for connecting the banister-rail and newel-posts, and to produce other improvements, which will be more specically pointed out hereinafter. These objects we accomplish in the manner illustrated in the acccompanyin'g drawings, in which- Figure l is a view in elevation of our iinproved stairway. Fig. 2 is a central vertical section of a portion of the central supportingtube. Fig. 3 is a central sectional view of a portion of one of the newel-posts, showing the manner of connecting therewith the banister-rail. Fig. 4 is a central sectional View of the lower portion of the central supportingtube and its supporting base-plate. Fig. 5 is a detail view in perspective of the inner end portion of one of the vertical step portions. Fig. 6 is an enlarged sectional view taken on line a: of Fig. l and being a central sectional view through one of the vertical step portions and a portion of the central supporting-tube, and Fig. 7 is a transverse section of the two step portions.

Similar letters refer to similar parts throughout the several views.

In forming our improved stairway we employ, as shown, a central vertical supportingstandard a in the form of a tube. The lower end of this standard is supported, as shown, within a suitable socket b, formed in the upper side of a base-plate b', the latter being adapted to be secured to the floor of a building.

c represents the vertical step portions, and c the horizontal step top portions, to the under side of which, near their forward edges,

are secured the upper edges of the portions c. Asis usual in this class of stairways, the top boards c of the steps gradually widen as they 5 5 extend outwardly from the central support. The inner end of each of the step portions c is provided, as shown at c2, with a plate or casting which is, substantially, in the form of an inverted L, the upper arm of said casting 6o being secured to and flush with the upper side of the step portion c. The vertical arm of the casting c2 extends, as shown, against the inner end of said step portion and is secured thereto by suitable screws c3. This vertical arm or end facing of the step portion c is provided with ltwo outwardly-projecting studs d, the latter having enlarged heads, as indicated.

The central tubular support a is provided, 7o as shown, with as many pairs of openings e in its periphery as there are vertical step portions c, the openings of each pair being arranged one vertically beneath the other, and said pairs being arranged spirally in said tube, as indicated in Fig. 2 of the drawings. Each of the openings e is of the usual keyhole t'orm--d e., consisting of a circular upper end, from which extends vertically downward a neck, (indicated at e3.) The inner end 8o of each of the step portions c is connected with the tubular standard a by inserting the heads of the casting-studs d through the larger ends of the openings e and dropping said step portion downward until the stems 8 5 of said studs are in the portions ea of said openings. In this mannerit will be seen that the step portions c are prevented by the bearing of the heads of the studs d against the inner side of the tube from dropping downward 9o or becoming loosened therefrom. The inner end of each of the top plates c of the steps is concaved to conform to the curve of the periphery of the central standard against which said top plate abuts.

f represents the side strin ger or side beam of our improved stairway, which is of the spiral form shown. This side beam consists of an inner vertical layer of wood f', on the outer side of which is secured a similar wood roo layer f2. p

f3 represents metallic plates or strips which extend throughout the length of said side beam, said plates being arranged at a distance, one above the other, in properly-shaped depressions formed in the outer face of the wood layer f2. These metal plates are by means of suitable screws or bolts, which are indicated at g, secured to the wood layer f and to the end of the step portions c, as indicated in Fig. 6 of the drawings. On the outer side of the wood layer f 2-is secured an outer layer, preferably of Wood, (indicated at g.)

g2 represents suitable beads which are secured to the face of the outer layer g', preferably adjoining the upper and lower sides thereof. Rising from the upper side of the beam f are suitable banisters 7c, the upper ends of which are connected by a suitable banister-rail k. The upper and lower ends of this rail 71; are secured, as hereinafter described, to the upper portions of newel-posts m,while the side beam f is secured tothe bases of said posts.

As indicated in Fig. 3 of the drawings, We provide in the upper portion of each of the newel-posts a socket or deprcssionp, the mouth of which is partially closed by a plate 19, havinga central slotted opening p2. To the inner side of the upper portion of the plate p we secure, as shown, the upper end of a downwardly-extending spring-strip p3, which extends to about the center of the height of the slotted opening p2. At each end of the banister-rail we provide a hook extension p4, which is adapted to enter the slotted opening p2 of the plate p and engage with said plate, as shown. In thus effecting a connection between the banister-railand newel-posts it will be seen that the lower end of the spring p3 will by contact with the upper side of the hook p4 operate to prevent such elevation of said banister-rail as may serve to admit of its withdrawal from the socket. Incase itis desired, however, to'separate the rail and post a slight inward `pressure upon the spring p3 by any desired tool inserted through the upper portion of the slot p2 will result in the disengagement of said spring with the hook of the ban-` ister-rail and admit of the latter being elevated and withdrawn. It is obvious that the upper newel-post may be supported upon the flooring or in any well-known or desired man ner.

From the construction herein shown and described it will be seen that a novel and reliable construction of a spiral stairway is provided, which will be exceedingly strong and durable and which may be produced in a neat and substantial manner at a reasonable cost of manufacture.

Having now fully described our invention, what ive-claim, and desire to secure by Letters Patent, is

l. In awinding or spiral stairway, the cornbination,with thecentral tubularstandard and theslotted openings e therein, of the step portions having projecting studs cl adapted to engage with said openings e, top step-plates c', and side beam, substan tally as and for the purpose specified.

2. In a winding or spiral stairway, the coinbiuation of the central tubular standard a, keyhole-shaped openingse, arranged spirally therein, step portions c, and studs cl, projecting from the ends thereof and having enlarged heads, said studs adapted to engage, as described, with said slotted openings e, substantially as and for the purpose specified.

3. In a spiral or winding stairway, the colnbination of the central tubular standard d, openings e therein, step portions c and c', studs d, projecting through said portions c and adapted to engage, as described, within said openings e, and spiral side beam f, consisting of two or more connected wood layers and intervening metallic plates f3, the 4latter being secured to the steps, substantially as and for the purpose specified.

HERMAN F. A. BORNEMAN. JACOB DAAB. In presence of- C. C. SHEPHERD, THOS. S. GATES.

srs 

